Initiated work on Database interface and User model
Added regex to match valid username to User
Changes
Merge branch 'update'
Started working on Add button functionality
Updated new address generation to accept a label.
Finished code for thread-safe database interface
Added basic documentation to Database, and added isValidUsername static method to User model.
More additions to User Model
Added account creation to User model, and ability to retreive who the user is
Added recoverPassword method to User model
Added LOGGED_IN singleton for currently logged in user, and added logout function (no button though)
Merging
Merge branch 'master' into story5
Added button to access address list from the main activity (should be removed later when the main layout is finalized)